Thread: 51 MG restoration.

I will repeat my dribble once again.
MSD like this will produce a hot spark for 20 degrees of rotation, give or take considering resistance, etc.
This means advance is out of the window for this period as spark will be present and not need to be advanced.

I would recommend disabling the vacuum advance as well. Checking total timing and desired will determine what advance could be tuned. FME it ain't gonna be ported/ manifold vacuum. Stiff springs on the weights wil get more advance as the mill is screaming.

Lock it all out and determine base timing (where it seems to run best).
Check total advance and see specs. (not that that matters!)
You might be surprised. Starts good. Rattles on accel, retard timing until rattle is gone. Binds on start? Too much advance. Heavier springs/lockout.
Hard to start? Retard timing til starts easily. No rattle up top? Window too narrow. Lighter springs.
You can change just 1 spring to get incremental.
Tuning.

In the UK there is a store called Halfords, it sells car tools and parts as well as other things.

I bought a kit there once, it was a sort of glass spark plug affair, that a person replaced a spark plug with (just for the test).

The idea was that a person could see the colour of the bang.

I can't remember why it said I needed to see it now but regardeless, I used to do my timing with a strobe lamp.

Nice explanation, Tom. Thanks for that. It makes full sense to me. I don't know the engine Mike is working with but I do know mechanical advance seems more accurate if needed. Here is to hoping no advancement is needed at all being it has such a wide range!

Ahh the ole colour tune system Steve.
Those lil glass windows were for setting optimal fuel mixture not spark.
Could dial in your mixture lean or rich based on combustion glow.
Still used in motorcycle worlds and old car racing I’d imagine.
And thanks for the write up Tom. Lack of any advance just seems wrong to me. I get what you are saying though so am eager to get her rolling again to get her dialed in.

Kindof strange to me at first. The spark is long in duration at idle/lower speeds and becomes a single spark at high RPM's.
In my Tiger, I use a stock 70's magnetic trigger dist with the springs changed to tight ones and stops added to limit advance on high RPM's, which it really never sees. 32 degrees total advance at 5500 RPM. NO vacuum advance.

The Cuda has a MSD dist which came fairly locked-out and no vacuum advance to use with the box. Same Magnetic pickup system.

That thing makes a nasty spark so too much total timing is wild. The Tiger had 98 degrees total advance when I started.
No power to start and rattled like crazy with little load.

Blew my mind but I began to understand what was happening as I messed with it and used an advance timing light to see what I was doing.
Began by disconnecting vacuum advance and changing springs to tighter ones. Finally added bushings to the weight stops until things got right. I would say it's basically locked-out.
MSD is the Best improvement I have done to that car.

Nowadays, I just lock the advance out and run it.

Once again reminded of one of the truly great things about this thread: I have absolutely *no* idea what the hell you guys are talking about, so I must be learning a bunch!



Such a great project, and such a great thread. Thanks to all who have chipped in!

Originally Posted by Cangooner

Once again reminded of one of the truly great things about this thread: I have absolutely *no* idea what the hell you guys are talking about, so I must be learning a bunch!



Such a great project, and such a great thread. Thanks to all who have chipped in!

Yeah, if I'm ever able to get a classic car I'm going to try and get it inspected by someone that knows what to look for so I don't get ripped off.

My Ford escape is almost 3 years old now and will be out of bumper to bumper warrantee soon, I've had since new so it's getting to be a classic.

I have to do loads of work on it. Wash, dry polish, hard work but but as MikeB52 will agree, it's hard work to keep our classics looking nice

Interesting how so many buy a classic and have no idea. They are used to things working.
Old cars were a challenge as they were new.

BIG shops, some with TV shows are backed-up for years. That's just around here.
Hopefully, I can get to the point where I can pick and choose on this old stuff.

Everything has to be redone at least 3 times. Chinese kits do not quality make..

Originally Posted by JP5

Yeah, if I'm ever able to get a classic car I'm going to try and get it inspected by someone that knows what to look for so I don't get ripped off.

Sage words!
I fell in love before logic prevailed on this car. Prolly should have done the same thing..
But,, maybe on the next one..